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Synthesis and characterization of new water soluble polymers composed of biocompatible/biodegradable building blocks.

機(jī)譯：由生物相容性/可生物降解構(gòu)件組成的新型水溶性聚合物的合成與表征。

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The synthesis and characterization of water-soluble zwitterionic poly(tyrosine), dendronized analogues of the same polymer, and non-ionic triethylene glycol (TrEG) -based dendritic macromoledules are investigated. Poly(tyrosine) linked through the phenol groups is synthesized under environmentally friendly conditions using tyrosine as the monomer and a polymer modified laccase as the catalyst. The chemoselectivity of enzyme used produces a unique unatural poly(amino acid) with phenylene and/or oxyphenylene linked backbone and free amino acid side groups. The amino-acid containing poly(tyrosine) has molecular mass Mw up to ∼82, 000 Da and displays reversible pH-responsive solution behavior. An isoelectric point (IEP) at pH 2.6 has been determined via measurement of zeta-potential. Chain conformation dependence on external pH due to intramolecular electrostatic interactions is manifested by the increase of hydrodynamic diameter Dh from 2.4 nm at IEP to 6.7 nm at pH 1.2 and 10 nm at pH 11.8.;In order to multiply the functionality of linear poly(tyrosine), hydrophilic dendrons are covalently attached onto the backbone to generate a new array of dendronized polymers. For this purpose hydrophilic dendrons and dendrimers are prepared divergently via a "click" reaction approach from hydrophilic and biocompatible building blocks: TrEG and bis-methylolpropionic acid (bis-MPA). Dendrimers up to third generation with precise structure have been successfully produced and characterized by NMR, MALDI-TOF, SEC, and DLS. The new poly(ether-ester) dendrimers up to Mn 15, 800 Da (G3) bearing two triazol rings at each branch site can also serve as a derndritic ligands for palladium (II) complexation. The catalytic capabilities of the complexes are confirmed by carrying out Suzuki-Miyaura reactions in aqueous media.;The modification of poly(tyrosine) into multi-functional dendronized polymer has been achieved through enzymatic polymerization of pre-formed macromonomers under environmentally benign conditions (45°C, in water). The dedronized polymers consisting of poly(tyrosine) backbone and TrEG based dendrons self-assembled in water to form aggregates with generation dependant morphologies.
機(jī)譯：研究了水溶性兩性離子聚酪氨酸，同一聚合物的樹突化類似物以及基于非離子三乙二醇（TrEG）的樹枝狀大分子的合成和表征。通過苯酚基團(tuán)連接的聚（酪氨酸）是在環(huán)境友好的條件下使用酪氨酸作為單體并用聚合物改性的漆酶作為催化劑合成的。所用酶的化學(xué)選擇性產(chǎn)生具有亞苯基和/或氧亞苯基連接的主鏈和游離氨基酸側(cè)基的獨(dú)特的天然聚氨基酸。含氨基酸的聚酪氨酸的分子量Mw高達(dá)?82，000 Da，并顯示出可逆的pH響應(yīng)溶液行為。通過測(cè)量ζ電勢(shì)已經(jīng)確定了pH 2.6下的等電點(diǎn)（IEP）。由于分子內(nèi)靜電相互作用，鏈構(gòu)象對(duì)外部pH的依賴性表現(xiàn)為流體動(dòng)力學(xué)直徑Dh從IEP的2.4 nm增加到pH 1.2的6.7 nm和pH 11.8的10 nm .;為了增加線性聚酪氨酸的功能），親水性樹突共價(jià)連接到主鏈上，以生成新的樹突化聚合物陣列。為此目的，通過“點(diǎn)擊”反應(yīng)方法從親水性和生物相容性的結(jié)構(gòu)單元：TrEG和雙羥甲基丙酸（bis-MPA）分歧地制備親水性樹突和樹枝狀聚合物。已經(jīng)成功生產(chǎn)了具有精確結(jié)構(gòu)的第三代樹枝狀聚合物，并通過NMR，MALDI-TOF，SEC和DLS進(jìn)行了表征。 Mn高達(dá)15、800 Da（G3）的新型聚醚酯樹狀聚合物在每個(gè)分支位點(diǎn)都帶有兩個(gè)三唑環(huán)，也可以用作鈀（II）絡(luò)合的樹突狀配體。通過在水介質(zhì)中進(jìn)行Suzuki-Miyaura反應(yīng)證實(shí)了該配合物的催化能力。;在環(huán)境良好的條件下，通過預(yù)先形成的大分子單體的酶促聚合作用，將聚酪氨酸改性為多功能樹突化聚合物（45） °C，在水中）。由聚（酪氨酸）主鏈和TrEG基樹枝狀分子組成的脫金屬聚合物在水中自組裝，形成具有世代相依形態(tài)的聚集體。

著錄項(xiàng)

  • 作者

    Wang, Lili.;

  • 作者單位

    State University of New York College of Environmental Science and Forestry.;

  • 授予單位 State University of New York College of Environmental Science and Forestry.;
  • 學(xué)科 Chemistry Polymer.;Chemistry Organic.
  • 學(xué)位 Ph.D.
  • 年度 2014
  • 頁碼 235 p.
  • 總頁數(shù) 235
  • 原文格式 PDF
  • 正文語種 eng
  • 中圖分類
  • 關(guān)鍵詞

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